1. Field of the Invention
The present invention relates to the field of liquid crystal displaying, and in particular to a backlight module structure.
2. The Related Arts
Liquid crystal displays (LCDs) have a variety of advantages, such as thin device body, low power consumption, and being free of radiation, and are thus of wide applications, such as mobile phones, personal digital assistants (PDAs), digital cameras, computer monitors, and notebook computer screens.
Most of the liquid crystal displays that are currently available in the market are backlighting liquid crystal displays, which comprise an enclosure, a liquid crystal panel arranged in the enclosure, and a backlight module mounted in the enclosure. The structure of a conventional liquid crystal panel is composed of a color filter (CF) substrate, a thin-film transistor (TFT) array substrate, and a liquid crystal layer arranged between the two substrates and the principle of operation is that a driving voltage is applied to the two glass substrates to control rotation of the liquid crystal molecules of the liquid crystal layer in order to refract out light emitting from the backlight module for generating images. Since the liquid crystal panel itself does not emit light, light must be provided from the backlight module in order to normally display images. Thus, the backlight module is one of the key components of the liquid crystal displays. The backlight modules can be classified in two types, namely a side-edge backlight module and a direct backlight module, according to the site where light gets incident. The direct backlight module comprises a light source, such as a cold cathode fluorescent lamp (CCFL) or a light-emitting diode (LED), which is arranged at the backside of the liquid crystal panel to directly form a planar light source supplied to the liquid crystal panel. The side-edge backlight module comprises an LED light bar, serving as a backlight source, which is arranged at an edge of a backplane to be located rearward of one side of the liquid crystal panel. The LED light bar emits light that enters a light guide plate (LGP) through a light incident face at one side of the light guide plate and is projected out of a light emergence face of the light guide plate, after being reflected and diffused, to pass through an optic film assembly so as to form a planar light source for the liquid crystal panel.
As shown in FIG. 1, which is a schematic view showing a conventional side-edge backlight module structure, the conventional side-edge backlight module comprises: a backplane 100, an LED (Light-Emitting Diode) light guide plate 300 arranged in the backplane 100, a light source 500 arranged at one side of the light guide plate 300 and mounted to a heat dissipation board 800, a mold frame 700 arranged above the backlight source 500 and the light guide plate 300 and mounted to the backplane 100, an optic film assembly 900 arranged on the light guide plate 300, a bottom reflector plate 200 arranged between a bottom board 130 of the backplane 100 and the light guide plate 300, a plurality of grid points 400 formed on a surface of the light guide plate 300 that is adjacent to the bottom reflector plate 200, and a reflector plate 600 arranged above the LED light source 500 and mounted to a corresponding portion of the mold frame 700.
The light guide plate 300 of the conventional side-edge backlight module structure is unitary. Due to constraints of the machine size and the manufacturing techniques, it is only possible to manufacture unitary light guide plates that are of relatively small sizes. Recently, the liquid crystal displays, especially liquid crystal televisions, is being developed toward being size enlarging (such as 110 inches) and thinning. Correspondingly, related optical components included in the backlight module structures must suit the need of size enlarging. However, the unitary light guide plates obviously do not meet such a need and further improvements are required in order to facilitate the development of the liquid crystal televisions toward even being larger in sizes and thinner.